Overview
ISO 15320:2011 specifies a laboratory test method for the determination of pentachlorophenol (PCP) in an aqueous extract of pulp, paper and board. Originally developed for paper and board intended to contact foodstuffs, the method is applicable to all types of pulp, paper and board. The method uses aqueous extraction (cold or hot), concentration by solid-phase extraction (SPE), chemical derivatization (acetylation) and quantification by gas chromatography with electron-capture detection (GC‑ECD) or gas chromatography–mass spectrometry (GC‑MS). The working range for acetylation is 0.05 mg/kg to 0.5 mg/kg.
Key topics and technical requirements
- Scope and sampling
- Applicable to pulp, paper and board; sample selection per ISO 186 or ISO 7213.
- Minimum sample required: 10 g (oven-dried); determine dry matter per ISO 638.
- Extraction
- Cold-water extraction: 10 g sample, 200 ml water, 24 h at (23 ± 2) °C.
- Hot-water extraction: 10 g sample, 200 ml boiling water, 2 h in 80 ± 2 °C water bath.
- Concentration and cleanup
- Solid-phase extraction using phenyl silica SPE columns (e.g., 500 mg/3 ml).
- Elution with n‑hexane into a potassium carbonate receiver.
- Derivatization
- Acetylation with acetic anhydride to form acetylated PCP for GC analysis.
- Quantification
- Internal standards: 2,3,6‑trichlorophenol for ECD; 13C6‑labelled PCP for MS.
- Calibration by plotting area ratio versus mass ratio; report results in mg/kg of material.
- Instrumentation
- GC conditions and detector settings are specified; GC‑MS can use SIM/SIR for sensitivity.
- Safety note
- Method involves toxic or corrosive reagents (PCP, methanol, acetic anhydride, sulfuric acid). Users must follow appropriate safety and environmental practices.
Applications and users
ISO 15320:2011 is intended for:
- Testing laboratories performing routine quality control and compliance testing of paper and board (including food-contact materials).
- Manufacturers and converters in the pulp and paper industry monitoring PCP residues.
- Regulatory bodies and certification bodies verifying conformity with chemical safety limits.
- Research labs conducting trace-level analytical development for chlorinated phenols.
Practical benefits: reliable, standardized approach for low-level PCP determination; adaptable for GC‑ECD or GC‑MS workflows; suitable for regulatory reporting and product safety verification.
Related standards
- ISO 186 - Sampling to determine average quality
- ISO 536 - Determination of grammage
- ISO 638 - Dry matter content (oven-drying)
- ISO 7213 - Pulps - Sampling for testing
- ISO 3696 - Water for analytical laboratory use
Keywords: ISO 15320:2011, pentachlorophenol, PCP, pulp paper board, aqueous extract, solid‑phase extraction, acetylation, GC‑ECD, GC‑MS, food contact materials.